Biochemical Validation of a Self-Administered Carotenoid Intake Screener to Assess Carotenoid Intake in Nonobese Adults

Background

Epidemiological studies have demonstrated an association between carotenoid intake and health. However, an accurate measurement of carotenoid intake is challenging. FFQ is the most commonly used dietary assessment method and is typically composed of 100-200 items. However, the greater participant burden that accompanies a more detailed FFQ provides only a marginal gain in accuracy. Therefore, a brief validated carotenoid intake screener is needed.

Objectives

To conduct secondary analysis evaluating the validity of a newly developed 44-item carotenoid intake screener from The Juice Study: Sensitivity of Skin Carotenoid Status to Detect Change in Intake (NCT03202043) against corresponding plasma carotenoid concentrations (primary) and skin carotenoids (secondary) in nonobese Midwestern American adults.

Methods

Healthy adults (n = 83; 25 men and 58 women) aged 18-65 y (mean age, 32 ± 12 y) with a BMI (in kg/m2) of 18.5-29.9 (mean BMI, 25 ± 3) were recruited between 25 April 2018 and 28 March 2019. Participants completed the carotenoid intake screener weekly during the 8-wk parent study. Plasma carotenoid concentrations were assessed at weeks 0, 4, and 8 using HPLC. Skin carotenoids were assessed weekly using pressure-mediated reflection spectroscopy (RS). Correlation matrices from mixed models were used to determine the correlation between carotenoid intake and plasma and skin carotenoids over time.

Results

The total carotenoid intake, as determined by the carotenoid intake screener, correlated with both the plasma total carotenoid concentration (r = 0.52; P < 0.0001) and the RS-assessed skin carotenoid concentration (r = 0.43; P < 0.0001). Correlations between reported intake and plasma concentrations of α-carotene (r = 0.40; P = 0.0002), cryptoxanthin (r = 0.28; P = 0.0113), and lycopene (r = 0.33; P = 0.0022) were also observed.

Conclusions

The results of this study demonstrate an acceptable relative validity of the carotenoid intake screener to assess total carotenoid intake in adults classified as those having a healthy body or those with overweight.

Smokers report lower intake of key nutrients than nonsmokers, yet both fall short of meeting recommended intakes

Smoking is a major risk factor in the development of preventable disease which may be due to a poorer diet and the reduced nutrient intake of smokers. Our objective was to compare and evaluate the reported intake of current smokers with that of nonsmokers among participants of a study evaluating stress and smoking. We hypothesized (1) that overall energy and nutrient intake would be reduced in smokers compared with nonsmokers and (2) that smokers would have increased noncompliance with Dietary Reference Intakes (DRIs). Men and women (smokers n=138, nonsmokers n=46) completed a 3-day diet record at baseline. Mean energy and nutrient intakes were stratified by smoking status and compared with DRI levels. The mean body mass index was 28.3±0.5kg/m2 for smokers and 27.2±1.0kg/m2 for nonsmokers. Compared with nonsmokers, the smokers reported lower intakes of energy, total polyunsaturated fatty acids, linolenic acid, docosahexaenoic acid, total sugars, calcium, iron, magnesium, phosphorus, potassium, vitamin C, riboflavin, niacin, pantothenic acid, vitamin B6, folate, vitamin A, and vitamin E. Smokers reported reduced compliance with the DRIs for iron, phosphorus, vitamin C, riboflavin, and folate compared with nonsmokers. Unlike other evaluations of smokers vs nonsmokers, we observed no difference in body weight between groups. Smokers and nonsmokers alike reported dietary intakes lower than the DRIs for many nutrients. However, the reported nutrient intake of the smokers was substantially lower than nonsmokers for key nutrients, and they were more likely to not comply with the DRIs for essential nutrients, placing them at increased risk of chronic disease.

First trimester vitamin D status and placental epigenomics in preeclampsia among Northern Plains primiparas

AIMS

As maternal vitamin D status has been associated with preeclampsia, the purpose of this study was to determine variations in DNA methylation patterns and associated protein expression in placental genes regulating vitamin D metabolism.

MAIN METHODS

A convenience sample of 48 pregnant nulliparous women, including 11 later diagnosed with preeclampsia, were recruited in this prospective study. Using a case-control design in two groups of women, we administered a food frequency questionnaire to determine vitamin D dietary intake. Laboratory measures included serum vitamin D levels (25[OH]D), DNA methylation patterns and protein expression in placental genes regulating vitamin D metabolism (1α-hydroxylase, CYP27B1; vitamin D receptor, VDR; retinoid X receptor, RXR) from placental tissue collected at delivery among those diagnosed with preeclampsia and those who remained normotensive throughout pregnancy.

KEY FINDINGS

There were no significant differences in vitamin D dietary intake or mean serum 25[OH]D levels, although the proportion of women with deficient 25[OH]D levels was higher in the preeclampsia group (46%) than the normotensive group (20%). Placenta samples from women with preeclampsia also had increased DNA methylation of CYP27B1, VDR and RXR genes with lower protein expression levels limited to RXR.

SIGNIFICANCE

Hypermethylation of key placental genes involved in vitamin D metabolism suggests uncoupling of processes that may interfere with placentation and availability of vitamin D at the maternal-fetal interface.

Nutrition marketing on food labels

OBJECTIVE

This research sought to determine how often nutrition marketing is used on labels of foods that are high in saturated fat, sodium, and/or sugar.

DESIGN AND SETTING

All items packaged with food labels (N = 56,900) in all 6 grocery stores in Grand Forks, ND were surveyed.

MAIN OUTCOME MEASURE(S)

Marketing strategy, nutrient label information, if the product was fruit/or milk based, and target age.

ANALYSIS

Frequency distributions were computed.

RESULTS

Forty-nine percent of all products contained nutrition marketing and of those, 48% had both nutrition marketing and were high in saturated fat, sodium and/or sugar (11%, 17%, and 31% respectively). Seventy-one percent of products marketed to children had nutrition marketing. Of those, 59% were high in saturated fat, sodium and/or sugar content, with more than half being high in sugar. The most commonly used nutrition marketing statements were "good source of calcium", "reduced/low/fat free", and "food company's health symbol".

CONCLUSIONS AND IMPLICATIONS

Nutrition marketing is commonly used on products high in saturated fat, sodium and/or sugar and is more often used on products marketed toward children than products marketed toward adults. Current food industry symbols may not be helping consumers select foods low in saturated fat, sodium or sugar.